Steering coupling for trailers



I 1 @et 4 927 B.. J. MURN STEERING consum; Foa TRAILERS Filed sept; 18.192e oct. 4,1927;

y 1,644,264 B. J. MURN STEERING ouPLING FOR TRAILERS' Filed sept. 18.1926 2 sheetsQsheez 2 "Z i 1% x e Patented Oct. 4, 1927.

UNITED' STATES BAsIL J. Munn,l or FOLEY, MINNESOTA.

STEERNG COUPLING FOR TRAILERS.

Application led September 18, 1926. Serial No. 136,277.

This invention relates to steering couplings for trailers andparticularly to steering couplings adapted to be used with four wheeltrailers.

It is an object of this invention to provide a steering coupling forfour traction 'trailers adapted to be secured topa draft vehicle'and toa trailer and adapted to operate to steer the front traction means ofthe trailer in such a manner that the trailer will take a turn in thesame manner as the draft vehicle.

It is a further obj ect .to provide such a device which will steer thefront wheels of a four wheel trailer in such a manner that the pathtaken by the front wheels of the trailer will follow the path taken bythe rear wheels of the draft vehicle in the same mannerthat the pathtaken by the rear wheels of the draft vehicle will follow the path takenvby the front wheels of the draft vehicle.

It is yet another object of the invention to provide a steering couplingfor trailers which will steer a trailer to turnthe same at a very sharpvangle as the draft vehicle to which the coupling is attached is turnedwhereby the vehicle with the trailer attached can be reversed and turnedaround in very short space.

Still another object is to provide a steering Y coupling fortrailersconiprising a swingable draw bar adapted to be secured to thetrailer and to the draft vehicle, a Yshaped camway adapted to be securedto the draft vehicle and means adapted to be operated by the swingingmovement of the draw bar and working in the camway for steering thefront wheels of the trailer as the draw baris swung.

'lhese and other objects and advantages of the invention will beapparent from thefollowing description made in connectionl with theaccompanying drawings, wherein like characters refer to the same orsimilar parts throughout the several views, and in which;

Fig. 1 is a plan 'view showing,V a portion of a chassis of an automobileand a portion of four wheel trailer with the preferred embodiment of thepresent invention applied thereto, the device of the invention and thefront end of the trailer being shown in full lines in one position andin dotted lines in another position; Fig. 2 is a view in side elevationof Fig. 1, certain of the parts being shown in section;

Fig. 3 is a plan view of one type of hitch that may be used, certain ofthe partsbeing broken away; and

Fig. 4 is a plan view of portions of certain of Jthe parts used.

Referring to theA drawings, the rear end' of the chassis of astandardrautomobile is illustrated including the rear wheels 5, rearaxle `6, cross springl 7, rear body bolster 8, radius rods 9 andlongitudinal frame ineinbers 10. A four wheel trailer is shown includingthe front wheels 11, rear wheels 52,

front axle 12, rear axle 53, a front body bolster 13, front radius rods14, steering spindies 15 having spindle arms 15'al thereon, tie rod 16connecting the spindle arms 15a, front spring 17, and body 18. The saidtrailer construction is of a type now commonly used with the exceptionthat in the present construction the spindle arms 15a areextendedforwardly from the front axle rather vthan rearwardly and the tie rod 16is placed forwardly ofthe front axle.

In accordance with the present invention a bracket 19 is securedpreferably b v U-clips 20 to the rear body bolster 8, of the auto-rmobile. The bracket 19 is formed from two arms bent rearwardly and thendownwardlyv therein the pivot 25. Keeper 26 is preferably secured topivot 25 between the bearings 24 and has downwardly extending forked'portions 26a adapted to lit at `either side of the hook 21 overthe sidesofthe eye of the eye strap 23. Handle portion 26b'is provided at the topof the keeper anda hook 27 is secured at the outer end of the handleportion, a tension'spring 28 being secured at one end to the hook 27 andat its other' end to an eye secured adjacent the rear portion of oneside of the bracket 19. A U-shaped'strap '29 is bolted or otherwisesecuredto the front body bolster' V13 of the trailer and has extendingtherethrough the shaft 30. Bearing block 31 is secured to the y rear endofthe draw bar 22 and a pair of braces 32 extend rearwardly from thebearing block 31 and are journaledon the shaft 30. A pair of strapsSlSbolted or otherwise securedj adjacent the rear end ofthe draw bar 22,extend rearwardly and outwardly from either side of the draw bar andhave their rear ends twisted andl ci-rcu-larly curved to form additionalbearingsfor the shaft adjacent the outer ends of the strap 2Q.

A pair of bars 84 are bolted or otherwise secured preferably to theouter sides of the longitudinal frame members 10 of the automobile andextend rearwardly therefrom. A channel shaped bar is pivoted at-itsangular ends respectively to the inner ends of the bars 34.. Asubstantially U-shaped framey 86 is` pivotally secured at the inner sideof the ends of its legs tothe outer sides of thex bar 84. Asubstantially U-shaped brace 87 lits snug against the channel shaped bar35 and is bolted thereto and to the legs of the frame 36. Accordingly,channel bar 85,. frame 36 and brace 87 are rigidly secured together andmounted for pivotal movement on the rear ends of bars 84. Secured tothefraine 36 and to the U-shaped brace 37 a Y-shaped cainway is forinechthelegs of the Y extending rearwardly and the base or stem of the Yextending forwardly. Said carnway is formed from two oppositelyrearwardly and outwardly curved bars 38 having angular portions securedto the brace 37. A V-shaped guide 39, the point of the V extendingforwardly is secured' by angular bent end portions to the sides of theU- shaped frame 3Gl adjacent the rear end thereof, the curve formed bythe V following the y contour of the two curved bars 88 and being spacedat all points equidistant froin the curved bars 38a The outer ends ofthe bars 3:8 are bolted or otherwise secured to the angularly bentportions of the V 89. A crank 40d has a vertical portion journaledwithin the bearing block 8l, a horizontal wardly at the forward end ofthe horizontal portion, the vertical; portion fitting within the camwayformed by the bars 88. A cana roller 4l is mounted on the forwardvertically extending portion ofthe crank 40, the cam, bei-ng of'slightly greater height than the height of the bars 88 and havinghorizontal flanges formed at top and bottoni thereof. An arm 42 extendsvertically upwardly from the channel shaped bar 85 above the height ofthe forward end of crank 40- and has secured thereto at its upper endone end of a tension spring 43, the other end of spring 48 vbeingsecured to a pin 44 extending through the upper end of the crank 40 vandholding the cain 41 on the crank 40. The rear end of crank 40 extendsdownwardly below bearing block 3l and has rigidlyy secured thereto thetubular clan'ip 45'.. An` arm 46 lits within clamp 45 and isi rig-idlyand. adjustably securable therein vby set screw 47. The rear end of arin46 has a ball formed thereon adapted to fit within a socket 48 securedto one end of a link 49. A similar socket 48 is secured at the 'otherendl of the link 49 and has fitting therein a ball portion 50 secured totie rodY Operation.

The device of the invention having been secured to an automobile orother vehicle and to a four wheel trailer in the'nianner described, theoperation of the device is as follows, the vehicle takes a corner.

Ac the front wheels of the draft vehicle are turned when thevehicle isgoing at a fair .speed tiere will be two forces acting upon the draw bar22 and on the trailer. The inertia of the trailer when `a left turn, forexainple,'is taken will tend to swing the trailer to the right, that isto say, the trailer will tend to continue inthe direction in which it isalready travelingv due to centrifugal force. rlhe draft force exerted bythe draft vehicle will tend to carry the trai-ler and draw bar to theleft. lnasinuch as the relative position of the draft vehicle'will bechanged in respect to the .draw bar and to the trailer the longitudinalaxis of the draft vehicle will assume an acute angle with the draw bar.That is, the draft vehicle will follow the curvature of the road, whilethe draw bar will. tend to continue in theoriginal direction of travel.As the draft vehicle swings to the left in respect to the draw bar, Cainroller 4l will contact the left curved bar 38 of the cainway and willbear-against the saine inoving outwardly, as further turir ingnioveinent of the .draft vehicle continues, towards the rea-r endof theleft arin 38 of the Y-shaped caniway. The front end of crank 4l) willaccordingly be turned to the right in respect to the draw bar, thereby'actuating arin 45, arni 49 and tie rod 16 toward the left causing thefront wheels 1l of the trailer .to be turned to the left inA respecttothe longitudinal axis ofthe trailer.

The an'iount of turn of the front wheels'of i lll) will beturned at all.vThe front wheels of the trailer will then be turned in the saine manneras the/'front wheels of the draft ve-jhicle, aA dl the trailer will takethe turn in the V lines in Fig. l illustrate the extreme position thatthe body and front wheelsof the trailer will take when the shortestpossible corner is turned. The trailer will cut the corner taken in theturn much closer than the draft vehicle. Accordingly, the speed of thetrailv er about the turn will be less than that of the draft vehicle,Adue to the fact thatthe trailer will take a shorter path in its turnthan the draft vehicle. There will thus be less danger of the trailertipping over than of the draft vehicle turning over as a turn is taken.Also due to the fact that the wheels of the trailer will cut in on thecorner from the path taken by the draft vehicle there will be nowhipping action produced on the trailer and thus the chief troublehitherto found in providing a satisfactory trailer coupling will beobviated.

Wlhcn the lead vehicle is again turned straight, upon arriving on astraightroad after a left turn, the longitudinal axis the vehicle willbe turned to more nearly conform to the longitudinal axis of the drawbar of the trailer, thereby causing crank 40 to swing to the left,turning the front wheels of the trailer towards the right as the vehiclecontinues in motion. The front wheels of the trailer will theneventuallyV follow directly behind the rear wheels of the draft vehicleas the straight path is continued. It

y will of course be understood that as a right turn is taken themovement of the lvarious parts of the device will be in just oppositedirections from that described. n

Due 'to the fact that frame 36 is pivoted to the bars 35 for vert-icalswinging movement and also to the fact that cam roller 4l is of greaterlength than the -width of the barsBS, the rear end of frame 36 may beraised or lowered without danger of any of the parts binding as ,bumpsare struck by either the lead vehicle or the trailer, or as the rearwheels of the lead Vvehicle strike different levels from thelfrontwheels of the trailer. The yhook and eye construction of the hitch willpermitswinging movement of the draw bar in either a vertical orhorizontal plane, so that the bar 40 may bev raised or lowered orturnedas bumps or various levels inthe road are reached. The ball andsocket oints on the arm 4G, link 49 and the strap 23 may be disengagedfrom hook 2l. Pin 44 may then be withdrawn from the upper endof thelcrank 40 and the upper-Sforward end of the crank slipped through thecam roller 4l.

Vhen the device is in operation spring 43 will tend to center the upperendof the crank 40 and the cam roller 4l' within the Y-shaped lcamwayand dueto the fact that the forward end of spring 43 is raised about therear end thereof the upper end of the crank 40 willy always tend to beraised upwardly.v Y l y W ith the present device, due to the fact thatthe* front wheels of the trailer will cut inwardly on a turn from thepath taken by the rear wheels of the draft vehicle it can be seen thatthe lead vehicle with trailer attached can be readily turned around invery short space. The lead vehicle with trailer 'attached can be readilybacked up and the trailer will be steered while the lead vehicle is'backing without any danger that the trailer will -be swung off the`road. If desired frame 36 and V-shaped member 39 may be entirelyremoved `from the device,

the purpose of said frame ,and member being l merely to brace andstrengthen the camway 38. If this were done the camway 38 would be moreheavily constructed. A

The relative degree ofturn of the front wheels of the trailer, as thecrank 40 is moved Va certain distance to the right or left of draw barQQmay be adjusted by unscrewing the set screw 47 on tubular .clamp 45 andsliding arm 4G forwardly or rearwardly through the clamp to position theball end vof arm 46-at greater or lessY distance from clamp 45. Thelength of the lever arm of arm'46 inayraccordingly rbe varied therebycausing greater or less movement of link 49, tie rod 16, spindles 15 andlwheels l1.

The device has been proved to be very 'successful and eflicient inactual practice. Although vthe inventor contemplates theuse of thedevice chiel'iy with four wheel trailers, it will, of course,beunderstood that the same can be used with two wheel trailers and will beequally effective for steering the saine. If 'desired a number oftrailers provided with the present steering coupling may be drawn onebehind another by a lead vehicle.

It will, of course, be understood that .various changesinay be made inthe form, details, arrangement and proportion of the various parts`without departing from the scope of applicants invention.

Vhat `is claimed is: Y l l l. A steering coupling for trailerscoinprising a draw bar adapted to'be pivotally secured at one end to adraft vehicle for swinging movement in respect to said draft vehicle,and. adapted to be secured at its other end to a trailer, means forsteering the front traction means of said trailer, and a single memberjournaled in said draw bar, connected to said steering means at one endand having its other end working in said camway, said camway being soshaped that said steering means will be positively moved to either theright or the left by said mem-` ber as relative swinging movement takesplace between said draw bar and said draft vehicle.

2. The structure defined in claim 1, and means for adjusting saidsteering means to vary the degree that said front traction means of saidtrailer will be steered said swinging movement between said draw bar andsaid draft vehicle takes place.

3. A' steering coupling for trailers com prising a draw bar adapted tobe pivotally secured atene eudto a draft vehicle for swinging movementinrespect to said draft vehicle and adapted to be secured at its otherend to a trailer, a substantially Y-shaped eamway seeurable to the draftvehicle, a member journaled in said draw-bar and having a portionthereof working within said camway, said member being adapted to be'turned as relative swingingmovement between said draw bar and saiddraft vehicle takes place, and meansv connected to said member forsteering` the front traction means ofthe trailer.

1l. A steering coupling for trailers comprising a draw bar adapted Ytobe pivotally secured at oneend to a draft vehicle for swinging movementin respect to said draft vehicle and adapted to be secured at its otherend to a trailer, a substantially Y,.- shaped camway securable to thedraft vehicle, a crank journaled in said draw bar, oneend of said crankhaving ka cam thereon working within said camway, said crank beingadapted to be turned as relative swing ing movement between said drawbar and said draft vehicle takes place, and means connected to the otherend of said crank for steering the front traction means of the trailer.A

5. The structure set forth in claim t, said steering means beingadjustable to vary the relative degree that said traction means ofthetrailer will be steered as said crank is turned. v

6. In combination with a draft vehicle, and a four wheeled trailerhaving a tie rod for steering the front wheels thereof, a steeringcoupling comprising a draw bar secured to the front end of the trailerand pivotally Secured to the draft vehicle for relative swingingmovement in respect thereto, a substantially Y-shaped camway secured tothe draftl vehicle, a crank journaled within said draw bar and having acam at one end thereof working within Vsaid camway, an arm secured tothe other end of .said crank and a link pivoted to said arm and to thetie rod of said trailer whereby asrrelative swinging movement betweenthe lead vehicle and said draw bar takes place, said camV will ride insaid camway to turn said crank and the front wheels of the trailer willbe turned. Y

7. In combination with a lead vehicle and a four wheeled trailer havingtherein a tie rod for steering the front wheels thereof, a

draw bar )ivotally secured at one end to said to said arm and alsoconnected by a ball andr socket joint to saidl tie rod.

8. The structure set forth in claim 7, the portion of saida-rm connectedto said link beingadapted to beV spaced at varying lengths from the lastmentioned end of said crank. j

9. A four wheeled trailer having incombination a body, steering spindleswith spindle arms thereon upon whichV the front wheels are journaled, atie rod connecting.

the spindle arms of the front wheels, a draw bar connected at one end tosaidv trailer-body and having an eye at its other end, a bracket adaptedto be secured to a draft vehicle having a hook thereon adapted to engagewith said eye, a spring pressed keeper adapted to be held over saideye'to holdth'e samein engagement with said hook, aY-shaped caniwayadapted to be secured to said draft ve-vk soy hicle, a crankjournaledwithin said draw V' bar, oneend of said crankhaving a camthereon adapted to workwithin said camway, an arm secured to the otherend'of said crank and a link pivoted vto said arm and to said draw bar,said cam being adapted to be moved toward the outer end of one of thelegs of said Y-shaped camway Yas relative horizontal swinging movementtakes place between said draft vehicle and said draw bar, whereby thefront wheels of the trai-ler will be turned. l

10. rllhe structure setv forth in claim 9, and

means for automatically centering said cam in the stem of said Y-shapedc'amway. e

in testimony whereof i affix my signature.

BASIL J. MURN. Y Y

